Saturday, December 7, 2019

Holiday project 2.0: Wallmap of the Universe

Something for the Holidays: Printable wall map of the universe with a d3-celestial sky map combined with a logarithmic chart of the whole universe from our Sun straight through to the big bang! Click on the images below to download large versions with 8000 px width, combined or in separate parts.

Stellar Wallmap:

Logarithmic universe:

Sunday, December 1, 2019

D3-Celestial Sky Color

[See part I: Geolocator.]

A new feature for my d3-celestial star map: A sky color gradient that shows the current sky state at the set time and date if the projection is hemispheric. No extra coding needed, just set daylight.show to true in the configuration of check "Daylight Sky" in the form. Time zone still needs to be set manually and horizontal refraktion isn't considered yet, so the result need not be entirely accurate.

Saturday, November 30, 2019

Solar System Missions Update 2019-12

Here's my map of all active and future Solar System Missions as of December 1st 2019.

Hayabusa 2 has departed asteroid Ryugu for Earth to return the samples it collected earlier on.

Further activity happens at asteroid Bennu, where OSIRIS-REx will select a sample collection site and rehearse the retrieval maneuver. Parker Solar Probe has another Venus flyby on the 26th.

The European Space19+ meeting last month green lighted a lot of solar system missions: The Asteroid impact investigation probe Hera that will launch in 2024, the Lunar sample return mission Heracles or European Large Lunar Lander (EL3) with a Japanese lander and a Canadian rover, and finally the Earth Return Orbiter (ERO) component of the Mars sample return mission with NASA.

Data, images and documentation are available on my space exploration history GitHub repository and the associated website.

Monday, November 18, 2019

D3-Celestial Geolocator

I was looking for a simple graphical location-selector, a globe that can be spun, zoomed in and clicked on to get an approximate location. I found none so obviously I had to make my own. A good starting point was planetary.js which already takes care of the spinnable and zoomable globe and is pretty easy to extend with plugins. See my fork for details about the mouse-actions plugin.

All the work is done in a callback function for the mouse actions mousedown and mouseup. We could just use click, but that would also cause a positioning update on dragging actions on the globe. Only updating when the mouse coordinates don't change between down and up takes care of that. The rest is pretty straight forward, take mouse coordinates, calculate geographic position with the d3.js function projection.invert, and if that is valid (i.e. inside the globe) update the geolocation of the sky view.

  globe.loadPlugin(mouse({
    onMousedown: function() {
      var x = d3.event.offsetX,
          y = d3.event.offsetY;
      position = [x, y];
    },
    onMouseup: function() {
      var x = d3.event.offsetX,
          y = d3.event.offsetY,
          format = d3.format("+.3f");
      if (position[0] !== x || position[1] !== y) return;

      var pos = this.projection.invert([x,y]);
      if (!isNaN(pos[0])) {
        // latitude, longitude convention is the opposite for sky coordinates
        Celestial.skyview({"location": [format(pos[1]), format(pos[0])]});
      }   
      return pos;
    }
  }));

Time zones are not taken into account yet, so the result is not necessarily valid. That will be fixed later, as well as putting a position marker on the globe, showing the current terminator between day and night, and optionally also show the current sky state on the current view changing between blue and transparent.

[See part II: Sky color.]

Wednesday, October 30, 2019

Solar System Missions Update 2019-11

Here's my map of all active and future Solar System Missions as of November 1st 2019.

This month or the next Hayabusa 2 will depart asteroid Ryugu for Earth to return the samples it collected earlier on.

In the last few Month US Moon exploration came to life a bit with lots of new missions announced, in preparation for the Artemis/Gateway program the NASA Commercial Lunar Payload Services (CLPS) funded Astrobotic and Orbit Beyond to deliver two landers to the lunar surface in 2021, and the VIPER (Volatiles Investigating Polar Exploration Rover, obviously) will explore the lunar south pole in 2022. And then there are lots of private announcements notoriously short on detail, so I struggle to put them in the list somehow, knowing I'll probably miss most of them anyway.

Also interesting this Month is the European Space19+ Meeting, where a lot of mission announcements are to be expected. And finally, the Earth/Sun L1 Near Earth Object observatory NEOCam seems to go ahead at last, renamed to NEOSM, as in NEO Surveillance Mission.

Data, images and documentation are available on my space exploration history GitHub repository and the associated website.

Monday, September 30, 2019

Solar System Missions Update 2019-10

Here's my map of all active and future Solar System Missions as of October 1st 2019.

The month Hayabusa will perform its last task at asteroid Ryugu, dropping off the Minerva II2 rover. In November or December it will depart for Earth to return the samples it collected earlier on.

Chandrayaan 2 is still in lunar orbit, sadly, the Vikram lander appears to not having survived its lunar touchdown. Still active on the lunar far side are Chang'e 4 and the Yutu 2 rover, presumably waking up for another lunar day of work.

Data, images and documentation are available on my space exploration history GitHub repository and the associated website.

Friday, August 30, 2019

Solar System Missions Update 2019-09

Here's my map of all active and future Solar System Missions as of September 1st 2019.

The month starts off with the next perihelion for the Parker Solar Probe right on the 1st. Chandrayaan 2 is now in lunar orbit and will deploy the Vikram lander for a lunar touchdown on the 9th.

Hayabusais still busy at asteroid Ryugu, dropping off 2 more target markers on the 5th, and maybe landing the Minerva II2 rover at the end of the month. More details in a press conference on the 24th.

Data, images and documentation are available on my space exploration history GitHub repository and the associated website.